Friction-clutch



(No Model.)

0. PLOHR.

FRICTION CLUTCH.

2 Shets-Sheet 1.

Patented Oct. 26, 1886.

WITN ESSES:

INVENTOR;

(Om By his .Htforneys,

(No Model.) 2 SheetsSheet 2. O. PLOHR.

FRICTION CLUTCH. No. 351,370. Patented Oct. 26, 1886.

WITNESSES: INVENTOR:

By his dzlorneys,

' N. PETERS. Photo-Lilhngnpher. Wahinmnn, n. a-

UNITED STATES PATENT OFFICE.

OTTO FLOHR, OF NElVARK, NElV JERSEY.

FRICTION-CLUTCH.

SPECIFICATION forming part of Letters Patent No. 351,370, dated October 26, 1886,

Application filed October 30, 1885. Serial No. 181,370. (No model.)

. fication.

This invention relates especially to that class of frictionelutches by which one rotary part is coupled to or uncoupled from another at will and without regard to the direction of rotation.

The object of my invention is to provide a clutch which shall be reduced to the utmost simplicity of construction and afford a strong and thoroughly-reliable connection between the driving and the driven part. I provide one of these parts with a flange, and the other is connected through interlocking projections and recesses with a divided ring, which is ex panded within the flange by spreading its opening or division in such manner that each half of the ring reacts against the other, whereby the clutch is adapted to hold in either direction, the strength of its hold depending not on the power being transmitted, but on the force which the operator applies to spread the ring.

The accompanying drawings show my improved clutch applied to a hoisting-drum.

Figure 1 shows the preferred form of my clutch in longitudinal mid-section. Fig. 2 is a transverse section thereof on the line 2 2. Fig. 3 is an elevation of the friction-ring removed. Fig. 4. is a plan of the right-hand end of the drum and its bearing on a larger scale, showing the clutch-operating mechanism. Fig. 5 is an end elevation of this bearin g and the clutch-operating mechanism. Fig. 6 is a transverse section of the latter mechanism, cut on the line 6 6 in Fig. 4; and Fig. 7 is an enlarged transverse section of the friction-ring, cut 011 the line 7 7 in Fig. Figs. 8, 9, and 10 are views corresponding, respectively, to Figs. 1, 2, and 3, and showing a modified construction.

In the drawings, let A denote the drum- 7 shaft of a hoisting-engine, B the drivinggear fixed thereon, O the pinion driving said gear and shaft, and D the winding-drum mounted looselyon said shaft. In hoisting,

the drum is coupled to the gear and shaft, and is revolved by them until the load is raised to the desired height. Then, when it is desired to lower the load, the drum is disconnected from the gear and revolves backward as the load descends, the motion being controlled by a brake.

I will first describe the construction shown in Figs. 1 to 7.

The gear-wheel B is formed with an annular overhanging flange, a, and within this is arranged the divided frietiouring E. This ring is divided at diametrically-opposite points into halves, as shown in Fig. 3.

F F are two expanding-pins, each of which is formed with a tapered orwedgc-shaped end,

which on being forced between the divided portions of the ring forces them apart, and so expands the ring and causesit to bind against the inner surface of the flange a. The ring E is connected to the drum D by means of driving-pins G G, fixed in the end of the drum and projecting into holes or sockets g g in the opposite halves of the ring. WVhen the ring is expanded, and so is locked to the gear B, it drives or carries the drum with it, through the medium of these pins G G. The sockets g g are preferably formed on radii at right angles to the line of division between the halves of the ring, as shown, thus connecting each half at its middle to the drum.

In order to steady the two halves of the ring E and keep their faces aligned, I provide it, by preference, with two keeper studs or bolts, 1) 1). Before dividing the ring I bore through it, on the line of the division, two rather small holes, to fit, or nearly so, the shanks of the studs I), and then counterbore these holes on each side to form recesses to receive the heads and nuts of the studs. The studs are passed through the holes, the heads of the studs fitting into the counterbored recesses on one side, and the nuts,which are screwed up to a shoulder on the stud-shank, fit into the opposite recesscs, These studs permit the ring to expand, but keep the faces of the two halves aligned, as will be well understood.

The stud might be double-headed, instead of having a head and nut, as it could be inserted laterally before the two halves are brought together; but I prefer to use aunt of circular form and nick it to receive a driver. The expanding-pins F F pass through the drum parallel with its axis, having bearings Their ends projecting beyond the in its ends. farther end of the drum are fastened to ayoke or cross-head, H, forming part of a sliding sleeve, I, which is mounted loosely upon the shaft A. The groove in this sleeve is engaged by a forked arm on aslide, J, and this slideis engaged by the short arm of a hand-lever, K. By pulling this lever the pins F F are pushed forward and the clutch is applied. I

The slide J and lever K are mounted in a bearing-frame, L, which is fixed, preferably, on the bearing-cap M of the bearing of shaft A. The frameLis slotted for the reception of afiat plate, m, which is slipped into it and fastened by is fulcrumed. The slide J has'a slot, j, into which the rounded bottom end of K projects, and it is by acting against the end of this slot that the lever pushes the slide forward. A small steel plate is dropped into the end of the slotj, as seen in Fig. 8, to take the wear of the lever. This mechanism for actuating the expanding-pins from the hand-lever is simple, easily constructed and put together, and avoids lateral and twisting strains as far as possible, thereby reducing wear and liability of breakage.

The employment of two expanding-pins, F F, arranged on opposite sides of the shaft equalizes the strain due to the thrusting in of the pins, and expands the friction-ring more uniformly than when but one pin is used. The pins are best placed about midway between the center and periphery of the ring, although when a small drum is used it may be necessary 'to place them closer together.

The ring E is peculiarly constructed in order partly to adapt it to the arrangement of the pins, and partly to equalize the expansion asfar as possible over its entire periphery. Each half or section of the ring is formed with bars or ribs b 1), extending from its pe-' riphery on opposite sides along the line of division to and a little beyond the expandingpin, and with diagonal ribs or braces c c, extending from the expanding pins toward the driving-pins. These braces transmit the press sure of the expanding-pins to near the middle of each half or section of the ring, thus forcing the sections outward from each other bodily. In order that the sections shall not be rigid, aswould be the case were they portions of a solid disk, I slit each section at f, thereby affording some elasticity, and in effectdividing the half-sections into quarters. The result of this construction is that the ring expands equally, or very nearly so, in all directions, so that the wear is uniform all around its periphery, instead of being greatest at and close to the line of division, which would otherwise be the case.

The inner surface of the flange a in the wheel B is turned true and .smooth, being preferably polished, and the. exterior of the ring is also turned true and polished. I make the ring of cast-iron, and after turning down its periphery I apply to the latter afacingstrip, 6, of copper, as best shown in Fig. 7. This is best held in place byrivets. The copper facing is thin, dressed smooth, and preferablypolished. I thus produce a frictional surface that, affords great adhesion when the ring is expanded, and which does not readily heat when the clutch is released and the ring is turning free within the flange.

When the winding-drum is necessarily of very small diameter, as compared with the driving-gear, I adopt the construction shown in Figs. 8, 9, and 10. Here only one pin, F,

is used, and this is placed as near as possible If it could come directly into.

to the shaft A. the center of the ring it would be even better. The ring is not severed into two sections, but is divided radially at one side only and slitted at f on the other side. Along this division the two ribs 7) b extend to the pin F, and thence the braces c c extend to the sides of the ring, joining thereto somewhat below the center. There are three driving-pins, G G, arranged as shown. The two upper ones should be given some slight looseness in their sockets g g to permit of the expansion of the ring. In other respects the construction is the sameas that first described, except that no studs 9 are required, as the ring E is not entirely divided in two.

Where the expanding-pins act upon the ring the latter is bored with a tapering hole, d, Figs. 3 and 10, half on one side and half 011 the other sidebf the division-line, and the expanding-pin is turned with a coned end,which is afterward dressed into the form of an ellipse in cross-section. The minor axis of this ellipse coincides with the line of division between the sections of the ring, so that the pin, when thrust in, acts only to spread the sections apart, there being no wedging action in the other direction.

My improved clutch is applicable to nearly every purpose for which friction-clutches are employed-such as connecting loosepulleys to their shaft, coupling oneshaft to another,

both in one-way and two-way clu'tches,

and also that in such clutches the sections of the divided ring have been expanded by wedges forced between them in a radial direction by pressure applied outwardly from between said wedges, and also that a split ring has had its opening expanded by a wedge pressed into it by a lever, the tail of this lever being thrown out by a cone sliding on the shaft. I make no claim to these constructions; and, further, I disclaim all friction-clutches wherein the power which is communicated from the driving to the driven partis transmitted through the expander for the friction-ring, and tends to expand the same, so that the hold of the clutch increases proportionately to the increase of the power transmitted through it.

I claim as my invention- 1. The combination,to form a friction-clutch, of a rotary part having an overhanging flange, a divided friction-ring within said flange, a rotary part connected to. said ring, whereby .both must rotate together, the axial shaft upon which said rotating parts are mounted, an expanding-pin arranged longitudinally along and parallel with said shaft, having a tapered or wedge-shaped end which enters between the divided parts of said friction-ring at right angles to the plane thereof, and adapted when thrust longitudinally toward the friction-ring to spread the sections thereof, and an operating-sleeve fixed to the opposite end of said pin and adapted to slide on said axial shaft, substantially as set forth.

2. The combination of a driving and a driven part, an annular flange formed upon one of said parts, a diametrically-divided frictionring within said flange and connected to the other of said parts, whereby either part may be driven from the other, an axial shaft upon which said rotary parts are mounted, and an expander for said ring, consisting of two tapered pins arranged parallel with said shaft,

4. The combination of a rotating part having an annular flange, a divided friction-ring within said flange,'another rotating part connected to and moving with said ring, an axial shaft upon which said rotating parts are mounted, an expanding-pin parallel with said shaft, having a tapered end entering between the divisions of said ringat right angles to the plane thereof, a sliding sleeve on said shaft secured to the opposite end of said pin, a slide mounted on a stationary part and moving parallel with the axis of said shaft and provided with a fork entering a groove in said sliding sleeve, and ahand-lever engaging and adapted to reciprocate said slide, substantially as set forth.

5. The combination of sleeve I, forked slide J, hand-lever K, frame L, plate m, and adj ustable back-stop a, substantially as set forth.

In witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

OTTO FLOHR.

Witnesses:

ARTHUR C. FRASER, GEO. BAINTON. 

